Already familiar are inlet gas supply modules comprising in addition a valve which permits the injection of a proportion of the exhaust gases emitted by the engine, referred to as recirculated exhaust gases, into the distribution box.
Such a distribution box thus permits a mixture of cooled air arriving from the heat exchanger and of recirculated exhaust gases arriving from the valve to be distributed towards the cylinders of the engine.
For this purpose, the distribution box comprises a cavity defining a space inside which the cooled air arriving from the heat exchanger and the recirculated exhaust gases arriving from the valve are mixed.
In order to inject the recirculated exhaust gases into this space, a distribution box of this kind includes an injection channel of substantially cylindrical form and pierced by a plurality of injection ports, or injectors.
Already familiar is a distribution box, of which the injection ports all have the same diameter and are arranged linearly along the injection channel opposite the cylinders of the engine, the admission of the gas into the injection channel taking place, via the valve, at one of the extremities of the injection channel.
It has been found that, in such a distribution box, as the recirculated exhaust gases advance inside the injection channel, the static pressure and thus the injection flow of the recirculated exhaust gases diminishes for each successive cylinder, with the result that the injection flows and thus the recycling rates and the temperatures of the gases are uneven between the cylinders. In addition, this may cause the obstruction of some of the injection ports by particles contained in the recirculated exhaust gases.